Easy Horn Excel Spreadsheet

[soho54]

I figured I would get this out of the other thread.

Here is an Excel spreadsheet that will help you design a few different things in Hornresp. (It is attached at the bottom.) It will model a single/multiple driver horn in TH, Nd, and OD configurations, in 3 or 4 sections. It will also do a BP type of quarter-wave resonator, and T-TQWT in a pinch.

Before I forget, let's thank Marshal Leach, Richard Long, and Tom Danley. They did all the real work.
The majority of the math I used can be found here: http://users.ece.gatech.edu/~mleach/.../HornPaper.pdf
Thanks go out to David McBean as well. Without his program there would be no need for this.



Working in -up to Office 2003 (at least,) and Open Office so far confirmed.

[soho54]

I just finished an overhaul, and removed a lot of old cells, and code that were hold overs from other versions. The second page now includes a box to alter the Speed of Sound used, and a section that will allow you to enter your own length, and width into the horn profile generator.

I also fixed a condition that could give a negative last segment length, so it shouldn't happen anymore.

As always questions, comments, bug reports, and criticisms are welcome.

[soho54]

Updated version.

Well I goofed.

Not being able to edit the posts is a pain. I uploaded the wrong version there. That one will not do multiple drivers.

Here is the one that will, or if you have the first already just undo protection on the second sheet with "soho" and copy/paste this into B15 "=Front!B10"

Sorry about that.

[Brian Steele]

Originally Posted by soho54

I figured I would get this out of the other thread.

Here is an Excel spreadsheet that will help you design a few different things in Hornresp. (It is attached at the bottom.) It will model a single/multiple driver horn in TH, Nd, and OD configurations, in 3 or 4 sections. It will also do a BP type of quarter-wave resonator, and T-TQWT in a pinch.

Before I forget, let's thank Marshal Leach, Richard Long, and Tom Danley. They did all the real work.
The majority of the math I used can be found here: http://users.ece.gatech.edu/~mleach/.../HornPaper.pdf
Thanks go out to David McBean as well. Without his program there would be no need for this.



Working in -up to Office 2003 (at least,) and Open Office so far confirmed.

Neat stuff.

Suggestion: Use a separate sheet to host data that can be cut'n'pasted into a text file that can then be imported into HornResp. Makes transfer of information from the sheet to HornResp much simpler.

[just a guy]

This spreadsheet is awesome. I tried to work my way through that Leach paper a year or two ago and couldn't quite get it. I've seen other spreadsheets/programs that automate Leach's math from that paper but none as useful as this one.

I can clearly see how you used Leach's work here, but not sure what parts you attribute to Long and Danley, could you elaborate?

[soho54]

Brian Steele,
Thanks, I'll look into it.

just a guy,

I can clearly see how you used Leach's work here, but not sure what parts you attribute to Long and Danley, could you elaborate?

Long helped develop the working Reactance Annulling equations. The stuff in Leaches original work needed some help. In the link above it includes a "letters to the editor" section where Leach acknowledges his help.

Danley is there for the TH parts. They were developed using his patent app, various posts on different forums, and my reworking of his commercial offerings. Looking at the sheet there doesn't seem to be a lot there, but his subs were the driving force behind the whole thing.

The BP TP design I came up with after playing around with some of GMs recent designs. I found a quick way to get decent results, and added it in. There is a "better" way using a lot more math, but it ends up almost the same as the output now.

The T-TQWR design was just something I figured out using the data the sheet already provided that was easy, and worked. I thought bjorno would get a kick out of it seeing it there.

The Nd/OD section was added just because it was so easy to add in. By using the TH horn positional data it isn't setup for the best Hyperbolic to whatever translation though. It is setup for an easy fold translation from HR. If you want to get crazy with your Nd/OD horn you need to do it manually.

F17 on the second sheet in the horns length. Take it *707 to get S3 from the S1. *707 again, and that is S2. Now go (length-(length*707))*707, that is S4 from S3. What's left over goes to L45. Now use the Custom Hyperbolic Horn inputs on page two to input those lengths from the throat to get a better HYP approximation.

[David McBean]

Originally Posted by soho54

I also fixed a condition that could give a negative last segment length, so it shouldn't happen anymore. As always questions, comments, bug reports, and criticisms are welcome.

Hi soho54,

1. Thanks for fixing the negative last segment length problem.

2. Have you considered automating the "-Make Equal-" requirement by deriving the High Corner frequency from the values of m and the Low Corner frequency?

This could be done relatively easily by entering the expression =A20-C20 in the 'Front'!E35 cell and changing the Sub TEST macro VBA procedure to the following:

Sub TEST()
Range("E35").GoalSeek Goal:=0, ChangingCell:=Range("B19")
Range("E42").GoalSeek Goal:=0, ChangingCell:=Range("E41")
End Sub

Would there be any downside to doing this?

3. Changing the value of Qes from 0.48 to 0.1 in the Version 5 default spreadsheet generates a macro VBA run-time error.

Kind regards,

David

[soho54]

Originally Posted by David McBean

2. Have you considered automating the "-Make Equal-" requirement by deriving the High Corner frequency from the values of m and the Low Corner frequency?
---
Would there be any downside to doing this?

I hadn't thought about it, but it could work. I think it might work better as a button though, just to leave a little fine tuning in there if needed. I'll check it out, thanks.

Originally Posted by David McBean

3. Changing the value of Qes from 0.48 to 0.1 in the Version 5 default spreadsheet generates a macro VBA run-time error.

I wasn't able to duplicate this problem. Mine went on as usual, and output a horn. Can I ask what program you are opening it up in?

Thanks for the input.

[soho54]

OK I added the button, It was interesting. I had to add some extra lines, but it works out pretty nicely.
Sub Button1_Click()
Range("G41").GoalSeek Goal:=301, ChangingCell:=Range("B19")
Range("G40").GoalSeek Goal:=0, ChangingCell:=Range("B19")
Range("e42").GoalSeek Goal:=0, ChangingCell:=Range("e41")
End Sub

G40=A20-C20 G41=1+B19

You raise HC temporarily, then set it correctly, and finally you have to run the length script again, as the original only work with manual changes to the sheet cells.

The trick is going from a design with a really low HC to one that needs a much higher one. Like say if I went from the default settings, and changed Qes to 1, optimized it, and then changed Qes back to .48. This will lead to a fault every time, as the original VB script to set the horn length can't hit zero.

If I can figure out an easy solution to this, the script errors should go away. The easy fix is to always bump HC up before changing drivers.

[soho54]

Update v5a is out.

There are Excel, and OpenOffice versions. The OO need Excel macro compatibility turned on until I get full StarBasic scripts going.

This version also adds a push button HC to Fo matching, if you dislike doing it manually. (It auto sets the two orange cells for you )

I also changed the Qmc from =10, to Qmc=(SQRT(F10+1)*B10)+2. It's a minor change, but though I should note it as it will change the output numbers by a small amount.